New technology tested on possum teeth enamel may help Waikato University researchers to pinpoint the origins of Maori human remains.
Te Papa Museum in Wellington has been responsible for the country's international repatriation efforts since 2003. It holds hundreds of bone fragments, and has recovered about 85 toi moko (preserved heads) from foreign institutions.
On Monday, Te Papa will receive 20 toi moko in a Paris ceremony and on Thursday will formally welcome them home to New Zealand.
The scrupulous records of some colonial collectors have made it relatively easy for some pieces to be reburied.
However, in other cases, grave robbers left no clues and research-ers have to trawl through ships' logs and other records for leads and to piece together journeys. Complicating matters is that slaves' heads were used and regional patterns in tattoos do not provide a reliable guide to origins.